Every 27 minutes someone, somewhere
receives an organ transplant. But every 2 hours 24 minutes,
someone dies still waiting for an organ donor to turn up. There
simply are not enough donor organs available for all the people
who need them, and if anything the problem is getting worse rather
than better.
As surgical techniques and immuno-suppressant drugs have improved,
transplant surgery is seen as the answer to more and more medical
problems. At the same time, the introduction of laws about the wearing
of seat belts, a reduction in drinking and driving, and improved
car safety standards means fewer people are being killed in road
accidents. Doctors are able to save the lives of more people who
are rushed into hospital – and all these things reduce the
pool of potential organ donors.
Some estimates put the proportion of people in the UK population
carrying a donor card as low as 10%. |
Whatever is done to raise people's awareness of the importance of
organ transplantation and the need for donors, the supply of donor
organs from people who have died will never match the number of people
needing transplants. Living donors are being used increasingly, but
they too are a very limited resource. It is because of this mismatch
of supply and demand that research has been going on into alternative
ways of providing organs for transplantation. One area of research
which has received a great deal of media attention and funding is
xenotransplantation. This is the transplantation into people
of organs from other species of animals.
Xenotransplantation is not actually a new science. In 1906 a French
surgeon, Mathieu Jaboulay, implanted a pig’s kidney into one
woman and a goat’s liver into another. They both died. But
in recent years scientists began to think that the use of xenotransplants
could solve two of the biggest problems of transplant surgery – the
shortage of donor organs and the problems of rejection.
Most of the research into using animals as a source of organs for
human transplants has been done using baboons and pigs.
In 1964 six patients received baboon kidneys, in 1984 a baboon
heart was transplanted into a baby girl, and in 1992 two patients
received baboon livers. All of the patients died within weeks of
their operation, but they did not die because they had rejected
their new organ. They died of infections which they could not fight
because of the high dosages of immunosuppressant drugs they needed
to take. However, baboons are not an ideal source of organs because
they reproduce very slowly, having only one baby at a time. They
also carry many viruses which could spread into the human recipient.
Also, because baboons are so similar to humans, many people have
ethical objections to using them as ‘donors’.
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